Book excerpt: EMDR is a psychotherapeutic approach developed for the treatment of PTSD, meanwhile, practicing clinicians have found the application of EMDR to be useful in treating patients who have experienced emotionally traumatic events, which they described as distinctive of their family-of-origin, their personal life history and their attachment relations. In this book the authors describe some of the basic aspects that therapists must understand in order to adequately apply EMDR in the more severe cases, including dissociative disorders, personality disorders and different types of complex traumatization.